A local electronics store sold 80 laptop computers in January. In February, the store’s laptop sales were of January’s sales. How many laptop computers did the store sell in February?
For sales stated as a percent of an earlier month’s sales, the earlier amount is the base, the amount counted as . Write the new total as a percent of that base, then enter the expression in Desmos. A percent above already includes the original amount, so don’t add it again.
Hints
- Hint 1
The base is the amount a percent is taken of; it counts as . The question compares February’s sales with January’s. Which month’s count belongs after of?
- Hint 2
A percent greater than can describe the whole new amount, not merely the added part. You don’t add the original count again. What percent expression gives February’s full count?
Step-by-step
Find the percent of January’s sales
Step 1Write February’s sales as a percent of January’s
January’s laptops are the base, the amount counted as . If is February’s count, the words of January’s sales give . The already includes January’s , so adding again would count it twice.
- Step 2
Calculate February’s count
Type in Desmos. It displays , so the store sold laptops in February. Choice C.